The present invention relates to a lid mechanism for a recording medium insertion opening. In particular, the present invention relates to a lid mechanisms constructed so that an overly great deformation of a lid, which may occur due to the lid being pressed by a recording medium at a time of insertion thereof, may be prevented.
One example of such a lid mechanism according to the related art will now be described. A recording/reproducing apparatus such as a magnetic disc apparatus uses a disc cartridge which contains a disc, used as an essential recording medium, such as a flexible magnetic disc. Such a disc cartridge is inserted into the disc apparatus so as to be loaded thereon. There, the disc cartridge is inserted into the disc apparatus by passing the cartridge through a disc insertion opening formed in a front bezel of the disc apparatus. This disc cartridge insertion action causes the magnetic disc in the disc cartridge to be loaded on a turn table provided in the disc apparatus. As a result of the magnetic disc's being loaded on the turn table, data can be written on the magnetic disc and can be read therefrom through the function of the disc apparatus.
There are two types of lid mechanisms for recording-medium insertion openings, according to the related art, as shown in FIGS.1 and 2. In FIG.1, a lid 1 is assembled in the front bezel 3 while in FIG. 2 the lid 1 is assembled in a frame 4 of the disc apparatus.
In FIG.1, the lid 1 has three shafts 2, respectively located at each side and at the lid's middle part. Each shaft is fitted into a supporting hole 3a formed on the front bezel 3. Thus, the lid 1 is rotatably supported on the front bezel 3. In this construction, as the disc cartridge, not shown in FIG.1, is inserted into the disc insertion opening 3b, the lid 1 is pressed and caused to move into the disc apparatus, by the advancing edge of the inserted disc cartridge. As a result, the lid is rotated into the disc apparatus about the three shafts 2 rotatably supported by the respective supporting holes 3a. This rotation action of the lid 1 causes the disc insertion opening 3b to assume the opening state thereof.
In FIG.2, the lid 1 has two sideward-projecting shafts 2, one projecting from each side thereof, which shafts are fitted into respective supporting holes 4a formed on the frame 4. Thus, the lid 1 is rotatably supported on the frame 4. After mounting the lid 1 onto the frame 4, backward projecting hook 5, one projecting from each side of the front bezel 3, are fitted into respective mounting holes 4b. The lid 1 causes the disc insertion opening 3b formed in the front bezel 3 to be either in its opening state or in its closing state by pivoting about the side shafts 2 rotatably supported on the frame 4.
Recently, it has become desirable to reduce a thickness of such a disc apparatus. In order to reduce the thickness, the member, constituting the front bezel 3, located above the disc insertion opening 3b should be made smaller. In order to make this member smaller, the supporting hole 3a for the shaft 2 mounted on the middle part of the lid should be eliminated in FIG.1. In order to thin the disc apparatus further, a volume located to an axis mechanism is made smaller, the axis mechanism comprising the shafts 2 and the supporting holes 3a. Further, concerning a state of the lid 1 where the lid 1 is open, the thickness of the lid 1 should be made thinner. Consequently, as mentioned above, the supporting hole 3a for the shaft 2 mounted on the middle part of the lid should be eliminated in FIG.1.
Therefore, the lid mechanism for the recording-medium insertion opening as shown in FIG.2 tends to be used in many cases. The construction of FIG.2, however, has the following problems. As the lid 1 is rotatably supported by the axis mechanism including only the shafts 2 located at each side of the lid 1, the structural strength of the middle part of the lid 1 may not be sufficiently strong. Further, as the thickness of the lid 1 is made thinner as mentioned above, the structural strength throughout the lid 1 is reduced.
Such reduction in the structural strength of the construction of the lid 1 may cause the following problems. The lid 1 may become warped in shape, as shown in FIG.3, due to being pressed by the disc cartridge 6 (drawn by dashed lines) at the time of disc cartridge insertion through the disc insertion opening 3b of the bezel 3. Such phenomena may occur as a result of the disc cartridge 6 being inserted in a manner such that the advancing edge of the disc cartridge 6 is not in parallel to the rotational axis, of the lid 1, corresponding to a straight line connected between the two shafts 2, for example. As a result of such an insertion operation, the lid 1 may become deformed so that the middle part thereof projects into the disc apparatus. Such a warping deformation of the lid 1 may cause the shaft(s) 2 of the lid 1 to become removed from the supporting hole(s) 4a of the frame 4.